1. Field of the Invention
The present invention refers in general to the field of recycling of used cooking oils.
The present invention in particular refers to a process for valorization of previously collected and eventually filtered used cooking oils, by means of mixing a respective quantity of used cooking oils together with a corresponding quantity of a solidifying composition including a substance of the wax type or similar, so as to obtain a substantially homogeneous substance resulting from the mixture of both quantities. Moreover, the present invention refers to a mixing device for carrying out the process according to the invention.
2. Background of the Invention
The use of oils in cooking, particularly for frying, raises several environmental issues, in particular after their use and regarding their disposal. In this context, the possibility of valorization of used cooking oils at the point of use presents several advantages, because it avoids the logistic required for collecting used cooking oils to a central recycling or disposal location, and because it represents an additional source of economic value, allowing consumers to use a basic material for obtaining other materials or products for other uses and benefits.
However, processes for recycling used cooking oils in a domestic, or small scale commercial setting, whether this is that of a household or that of a restaurant, are conditioned by several technical and functional constraints. It is therefore particularly important that a process for recycling used cooking oils in such settings presents a set of characteristics, notably in terms of easy use (in particular, simple handling of raw materials involved) and in terms of general efficiency (in particular, obtaining the intended quality with the least energy use by the process). The present invention refers in particular to this last aspect.
In the scope of the present document, the expression “used cooking oils” refers to oils used in food in general, independently of their origin or production, for dressing or cooking, such as for example frying, or other uses, whereby oils are used or exceed their use deadline, and loose food grade value, being therefore available and suitable for recycling or final disposal. Within the meaning of the expression “used cooking oils” are further considered food oils in the liquid or solid state, as well as other substances of the fat type presenting characteristics similar to food oils.
Related Art
Processes for valorization of used cooking oils together with a solidifying composition are known in the state of the art.
In fact, the author has previously researched and developed the concept of recycling used cooking oils into candles, by means of their mixing together with a composition of solidifying substances, including waxes and similar substances. In particular the author has registered the PT 103856 thereby disclosing several functional aspects of a machine for producing candles based upon the processing of used cooking oils together with a solidifying composition provided in the form of a capsule. The PT 103856 does not disclose particular characteristics of the mixing process of a quantity of used cooking oils with the capsule of a processing composition, notably in terms of respective main steps, in view of maximizing respective energy efficiency while simultaneously ensuring a high quality level of the mixing process the aforementioned document also does not disclose particular aspects relating to the processing device included in the apparatus, notably in view of maximum energy efficiency associated to the mixing process.
The WO 2010/102370 A1 discloses an apparatus of domestic use for producing soap by means of recycling used cooking oils. This document points to the supply of the different compounds separately from the used cooking oil. Moreover, both the thermal and the mechanical energy to be provided during the mixing process are not generated by internal means of the apparatus in which the mixing device is integrated.
The aforementioned documents therefore do not disclose solutions in terms of the mixing process and of the device in which the mixing process takes place, in view of maximizing the energy efficiency and minimizing the time required for the process to be concluded, while simultaneously ensuring a high quality level of the mixing process, as well as particular safety conditions thereof.
In fact, using used cooking oils as raw material for the production of a new product with a new application, raises several technical issues, most of which relating to the highly contaminated and variable nature of “used cooking oils”, as this may be available at a given household or small commercial establishment. In particular the production of candles, or other solid compositions, by means of mixing used cooking oils together with a solidifying composition, raises several particular issues as to the result of the inherent mixing process. In the case of manufacturing of candles, one specially considers the requirement of obtaining a product presenting structural stability at ambient temperature, of homogeneous structure and aspect, of regular and inasmuch as possible complete burning behavior, and, in particular, observing the applicable safety standards and regulations.
In this sense, the author has carried out several tests that have demonstrated that the global efficiency of mixing such a solidifying composition together with a quantity of used cooking oils, and the final quality of the product resulting from such a processing, largely depend upon the evolution and steps carried out in the mixing process.
The author has similarly researched different configurations of the mixing device, as well as possible dispositions for its main energy delivery means, thereby establishing a set of embodiments that are regarded as more advantageous for carrying out the mixing process.